Quick Answer: How Do You Get Rid Of Intermodulation Distortion?

How are intermodulation products generated?

If a number of signals are passed through a non-linear device the result will be intermodulation products that are spurious frequency components.

The non-linearities cause each signal to combine with the other signals in the set.

to produce a series of second order sum and difference products, third order products etc..

Why intermodulation distortion happens in a satellite transponder?

Intermodulation distortion occurs when many carriers access a non-linear satellite transponder. … In this paper, the satellite C/I ratio is investigated when the transponder is accessed by many small carriers in the presence of a dominant carrier. A lower bound C/I ratio and an optimum input backoff point are deduced.

What is intermodulation noise?

intermodulation noise – Computer Definition Noise that is the result of modulation, demodulation, and any nonlinear characteristics of the transmission medium or transmission system components. See also modulation and noise.

What are three types of interference?

Interference of WavesInterference. Interference is what happens when two or more waves come together. … Linear superposition. … Constructive interference. … Destructive interference. … Reflection of waves. … Standing waves. … String instruments and transverse standing waves.

What is Carrier swing?

[′kar·ē·ər ‚swiŋ] (communications) The total deviation of a frequency-modulated or phase-modulated wave from the lowest instantaneous frequency to the highest instantaneous frequency.

How can intermodulation distortion be reduced?

Low pass or high pass filters may be appropriate in cases where the frequencies are disparate. Ultimately, the best solution is probably a band pass filter centered on the desired transmit frequency. Such filters can be thought of as high pass filter cascaded through a low pass filter.

What is PIM interference?

PIM is a form of intermodulation distortion that occurs in components normally thought of as linear, such as cables, connectors and antennas. … PIM shows up as a set of unwanted signals created by the mixing of two or more strong RF signals in a nonlinear device, such as a loose or corroded connector, or nearby rust.

What are the harmonics of a frequency?

Harmonics are voltages or currents that operate at a frequency that is an integer (whole-number) multiple of the fundamental frequency. So given a 50Hz fundamental waveform, this means a 2nd harmonic frequency would be 100Hz (2 x 50Hz), a 3rd harmonic would be 150Hz (3 x 50Hz), a 5th at 250Hz, a 7th at 350Hz and so on.

Where does intermodulation occur?

Most intermodulation occurs in a transmitter’s nonlinear power amplifier (PA). The next most common mixing point is in the front end of a receiver. Usually it occurs in the unprotected first mixer of older model radios or in some cases an overdriven RF front-end amp.

What is meant by total harmonic distortion?

The total harmonic distortion (THD or THDi) is a measurement of the harmonic distortion present in a signal and is defined as the ratio of the sum of the powers of all harmonic components to the power of the fundamental frequency. Distortion factor, a closely related term, is sometimes used as a synonym.

How much loss is considered acceptable in the antenna system?

While different systems have different acceptable return loss limits, 15 dB or better is a common system limit for a cable and antenna system.

What causes intermodulation distortion?

Intermodulation is caused by non-linear behaviour of the signal processing (physical equipment or even algorithms) being used. … The same nonlinear system will produce both total harmonic distortion (with a solitary sine wave input) and IMD (with more complex tones).

What is intermodulation distortion in amplifier?

Intermodulation Distortion can occur when two or more signals are mixed through a non-linear amplifier device. Each of the tones interacts with each other, producing altered (or modulated) amplitudes. This results in the formation of frequencies (often referred to as “sidebands”) not present in the original signal.

What is imd3?

Acronym. Definition. IMD3. Third-Order Intermodulation Distortion.

What is IF and RF?

An RF (or IF) mixer (not to be confused with video and audio mixers) is an active or passive device that converts a signal from one frequency to another. … These three ports are the radio frequency (RF) input, the local oscillator (LO) input, and the intermediate frequency (IF) output.

What is frequency distortion?

[¦frē·kwən·sē di′stȯr·shən] (electronics) Distortion in which the relative magnitudes of the different frequency components of a wave are changed during transmission or amplification. Also known as amplitude distortion; amplitude-frequency distortion; waveform-amplitude distortion.